#type("abc") →
#type([1,2,3])
#string1="abcdefg" → string1[0]="a"   string[2:5]="cde" string1[:5]="abcde"
#string1[5:]="fg"  string1[-2]="f"   string1[-4:]="defg"   string1[:-4]="abc"
#string1[1:-3}="bcd"
#string1[-3,1]不可以，因为其中是反序
#"abc"+"def"="abcdef"
#"abc"*3="abcabc"
#[1,10]*3=……


#"1"in "12345" →True
# 1 in [1,10] = True

# 1 not in [1,10] =False



#min("abc") → "a"

#min("京己路")
#'京'

#sum([1,2,3]) = 6

#s = "ppt ppt"
#s.index("p") = 0
#s.find("s") = -1(仅能发现第一个并输出位置）
#s.replace("p","q") = "qqt qqt"

#s.split() = ["ppt","ppt"]

#p = "qf3fgfgf"
#p.split("f") → ["q","3","g","g"]

#len([1,2,3)=3
